1. Field of the Invention
This invention relates generally to aerostat amusement devices and method of operation, and more particularly to a ballast device adapted to be secured to a toy balloon filled with a buoyant gas, the ballast device being in the form of a deformable squeeze container having a small opening defined therein and adapted to meter a liquid through the opening in precise quantities to afford careful adjustment of the ballast in the container to, in turn, precisely counter the buoyant force of the balloon.
2. Description of the Prior Art
Lighter than air devices are of course well known. Functionally, such devices utilize the displacement of an atmospheric volume by a lighter gas contained within a bladder, such as a balloon, to provide a lifting force. For most purposes, such devices may be divided into large "working" balloons adapted to lift individuals or cargo, and toy balloons which may be utilized for amusement, display or other ends in which the ability of a small article to float through the air is of concern. With regard to the toy balloon usage, the balloons were either permitted to fly away through the atmosphere, usually in a mass release of balloons for a display effect, or the balloon would be tethered by a string to preclude free flight. While a weight might be tied to a toy balloon, the small diameter of the buoyant gas molecules, such as helium, would cause sufficient leakage of the buoyant gas in a relatively short time to upset any equibrium initially reached by the weight offsetting the buoyant force of the toy balloon.
Adjustment of ballast in large, working lighter than air devices has of course been highly developed. Heavy flowable materials, such as metal, sand or water, have been included in such devices to permit manual or automatic release of ballast to control the buoyancy of the lighter than air device. In addition to a leakage problem of the buoyant gas, which is of less concern in most large balloons, other more fundamental problems such as expansion or contraction of the buoyant gas in response to heating or cooling, and changes in the atmospheric pressure as a result of substantial changes of altitude, are involved. Accordingly, ballast devices such as taught in the Cray U.S. Pat. No. 1,538,974, or the Winkler U.S. Pat. Nos. 2,983,950 and 3,063,598 have been designed. As with many other teachings relating to working--as opposed to amusement--lighter than air devices, such ballast systems are involved, expensive, and entirely inappropriate for the smaller toy balloon structures to which the instant invention is directed.